GlClear

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Revision as of 06:06, 30 April 2022 by SMcNeill (talk | contribs) (Created page with "'''_glClear:''' clear buffers to preset values {{PageSyntax}} :: SUB _glClear (BYVAL mask AS _UNSIGNED LONG) :: void '''_glClear'''(GLbitfield {{Parameter|mask}}); {{PageParameters}} * ''mask'' that indicate the buffer OR buffers to be cleared. The three masks are _GL_COLOR_BUFFER_BIT, _GL_DEPTH_BUFFER_BIT, and _GL_STENCIL_BUFFER_BIT. {{PageDescription}} * _glClear sets the bitplane area of the window to values previously sele...")
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_glClear: clear buffers to preset values


Syntax

SUB _glClear (BYVAL mask AS _UNSIGNED LONG)
void _glClear(GLbitfield mask);


Parameters


Description

  • _glClear sets the bitplane area of the window to values previously selected by _glClearColor, glClearDepth, and _glClearStencil.
  • Multiple color buffers can be cleared simultaneously by selecting more than one buffer at a time using _glDrawBuffer.
  • The pixel ownership test, the scissor test, dithering, and the buffer writemasks affect the operation of _glClear. The scissor box bounds the cleared region. Alpha function, blend function, logical operation, stenciling, texture mapping, and depth-buffering are ignored by _glClear.
  • _glClear takes a single argument that is the bitwise OR of several values indicating which buffer is to be cleared. The values are as follows:
_GL_COLOR_BUFFER_BIT: Indicates the buffers currently enabled for color writing.
_GL_DEPTH_BUFFER_BIT: Indicates the depth buffer.
_GL_STENCIL_BUFFER_BIT: Indicates the stencil buffer.
  • The value to which each buffer is cleared depends on the setting of the clear value for that buffer.


Template:PageNotes

If a buffer is not present, then a _glClear directed at that buffer has no effect.


Template:PageErrors

Template:KW is generated if any bit other than the three defined bits is set in mask.


Template:PageUseWith

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See also


Template:PageCopyright